Ha!! That's right! It has to be caffeinated instant coffee for Caffenol-C to work. Don't be tasting the chems!

Valerie, Digital Truth has an easy version of Caffenol-C (ie US version in teaspoons and oz) below, I think your students will have a ball learning about such an organic developer, that is green no less, which students are pretty attuned with, then when I was in school...

http://www.digitaltruth.com/data/caffenol.php